[osg-users] LineSegmentIntersector and MODEL Frame

OpenSceneGraph Users osg-users at lists.openscenegraph.org
Mon Feb 3 00:06:01 PST 2020

Hi Chris,
I guess you want the scene to accept the IntersectionVisitor, not the

On Sat, Feb 1, 2020 at 1:18 PM OpenSceneGraph Users <
osg-users at lists.openscenegraph.org> wrote:

> I have a scene built with a few objects loaded, the most pertinent one
> being a large plane surface centered at the origin. I want to cast a ray
> from a particular point at a particular angle inside the scene and get a
> list of everything it intersects—both the point of intersection and the
> Node object. Most examples of using intersectors involve picking from the
> window, so I haven't seen exactly what I wanted. But from what I've read,
> the following should at least be close:
>     Vec3d start( 0.0, 0.0, 100.0 );
>     Vec3d end( 0.0, 0.0, -100.0 );
>     ref_ptr<LineSegmentIntersector> intsec = new LineSegmentIntersector(
> Intersector::MODEL, start, end );
>     IntersectionVisitor iv( intsec.get() );
>     viewer.getCamera()->accept( iv );
>     cout << intsec->containsIntersections() << endl;
> My start and end points in this snippet are well above and well below the
> surface object. So that plane object should definitely be intersected by a
> line running between them. However the containsIntersections function
> always returns false.
> Immediately after making this preliminary test pick, the program calls
> viewer.run() so I know everything is arranged as expected in the scene. So
> my guess is that I'm missunderstanding how the visitor works. Perhaps the
> accept() function is not what I should be using to execute the intersector?
>  ~ Chris
> --
> You received this message because you are subscribed to the Google Groups
> "OpenSceneGraph Users" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to osg-users+unsubscribe at googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/osg-users/58d20034-cb65-4bef-937f-f85a1fa92030%40googlegroups.com
> <https://groups.google.com/d/msgid/osg-users/58d20034-cb65-4bef-937f-f85a1fa92030%40googlegroups.com?utm_medium=email&utm_source=footer>
> .
> _______________________________________________
> osg-users mailing list
> osg-users at lists.openscenegraph.org
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openscenegraph.org/pipermail/osg-users-openscenegraph.org/attachments/20200203/9e5b6745/attachment.html>

More information about the osg-users mailing list